Antiskidding device



April 8 1924.

M. J. DAVIS ANTTSKIDDING DEVICE (lriginal Fill-7:?! March 2.1 1922 Nov INV TOR I p f M v ATTORNEY Reissued Apr. 8. 1924.

UNITED STATES PATENT OFFICE.

MICHAELJ. DAVIS, 01? BROOKLYN, NEW YORK.

ANTISKIDDING DEVICE.

Original No. 1,440,660, dated January 2, 1928, Serial No. 545,624, filed March 21, 1922. Application for reissue filed December 31, 1923. Serial No. 683,829.

To all whom it concern:

Be it known that I, MICHAEL J. DAVIS, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Antiskidding Devices; and I do hereby declare the'following to be a full, clear, and exaoti description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates essentially to a device for stabilizing the steering mechanism and front wheels of a motor vehicle tie the end that lateral slip or skidding of the rear wheels is prevented. The device comprises a combination of cooperating members connected between the chassis and the steering mechanism, the character of the members being such that the distortion of the chassis and the relative displacement of the chassis and steering mechanism, caused by the forces which tend to produce side slip or skidding of the rear wheels, causes the device to function so as to prevent skidding.

It is well known that when the steering gear of a common motor vehicle is given a sudden or sharp inclination, it causes the rear of the vehicle, especially on a-slip'pery roadway, to side-slip; and it is-the chiect of the present invention to obviate this by means of a device associated with the steering gear and the vehicle chassis. Experience has shown that when the rear of a motor vehicle skids, the alignment of the front wheels with respect to the vehicle chassis changes; and it is also true that the rear oi" the vehicle will not side-slip or skid if the position of the front wheels with respect to the chassis can be maintained constant. If the front wheelsare held so that the rear of the vehicle cannot pivot on them, the vehicle may slide as a whole, or continue in the direction thefront Wheels are headed.

In order to acquire a proper understanding of this invention, it is necessary to core sider the fact that just prior to the instant when therear wheels of a vehicle start to skid, the'body of the vehicle is tilted, and the .hassis is distorted and displaced with respect to the steering mechanism and front Wheels. The forces which produce this displacement are of considerable magnitude,

and are exerted in such a manner that the displacement produced is eccentric or irregular.

In view of the facts outlined above, it is evident that skidding of the rear wheels of a vehicle may be prevented by a device responsive to the relative displacement of the chassis and steering mechanism, this device acting to prevent the forces tending to produce skidding, from effecting a change in the position of the front wheels with respect to the chassis. Experiments have shown that this can be accomplished by means of a device which exerts a com )aratively small force on the steering mechanism, at the proper instant.

In general, my invention comprises two frictio members, one of which is adapted to be fixer to the vehicle chassis, and the other adapted to he connected to the steering mechanism. These members are mounted on the vehicle in such a manner that, under normal conditions, they have no appreciable effect on the operation of the vehicle. The device is brought into play only when a relative displacementoccurs between the chassis and the steering mechanism, such as is caused by the forces tending to produce skidding, or by one of the front wheels striking an obstruction in the road.

The novel features of this invention are more fully described in the following detailed description, and illustrated in the accompan ving drawing. in which:

Fig. 1 is a plan view of the front part of a motor vehicle equipped with the improved device, and

Fig. 2 is a side elevation of the parts Shown in Fig. 1.

In the figures of the accompanying drawings, the numeral 5 designates a frame or chassis, and (3, (3 are the front wheels of motor vehicle. The front wheels 6, 6 are adapted to be oscillated to steer the vehicle in any direction by being mounted on knuckle joints 7 connected to an axle 8 which is yieldingly connected to the frame 5 by means of the springs 8. A cross tube 9 couples the two knuckle joints 7 together so that they will work in unison, to steer both wheels. A drag link 10 is actuated by a ated to steer the car, as-is well known.

crank ll tulcrumed at 1.2 to the chassis; and a hand wheel 14 with a worm 15 i-s-ugaging a pinion 16 mounted on'thc folcrinn is oper- As usually constructed, the drag link J3 is provided'at the points and with coil springs which absorb tile vilinations trans mitted through the knuchl icints 7, 'i from the front wheels 6.

In the embodiment of the invcht r. illustrated in the accompanyino draw-cm the means for preventing 7 p or skidding of the rear of the vehicle, comprises slink 17 connected'to the drag link 10 by means of the joint 24, thus forming an extension of the drag link. The friction members which I prefer to use, consist of a rack 18 and pin" ion 20, the pinion being rotatively connected to the link 17, and the being rigidly fastened to the chassis by any suitable means, such as the hangers or brackets 19; The rack may be mounted with the rack teeth projecting upward, as sh'oy i in the time ing, or the rack may be inverted and fixed to the chassis with the teeth fae. down ward. u shaped slide 21 guides the pinion 20 in a rectilinear path.

I prefer to make the iii f "i? cut of tubing so that it will be somewhat flexible,

and I also prefer to have the length of this member substantially equal to that of the drag link 10 so to have these parts properly balanced. The ll-shaped slide 21 may hang considerably below the rack 18, it may be in sliding contact therewith; This slide. should be wide enough and short enough. so ,hat when. the link 12'' is displaced laterally, the pinion let-ll: will bind in the rack teeth before the slide has an opportunity to bind on the es of the rack.

If the rack is mounted with its teeth era tending downward, the slide should hold the pinion 2-0 in fairly close contact with the rack teeth,

It is well lUlOX'll to those machine elcn'wnts that a rack ranged so that the pinion r, or is held in l the pinion and rack are in direct aiigg 'ninent. If the pinion is turned with respect to the rack, or if one side of the pinion is forced deep into the rack teeth, the pinion binds in the rackand relative movement of the rack and pinion is rendered practically inipossiblo. In the present invention I have utilized this characteristic oi? the rack and pinion combination to stabilize the front wheels of a motor vehicle, and to prevent the rear wheels from skidding,"

In order to understand the operation of this invention, one must bear in mind the fact that the several joints, for example those connecting the dra l i i 1th the knuckle '7 and with. the c ink 11, are noranally loose, and therefore will permit considerable, side play or late'al displacement of the link 17. 'Hu: forward and of the drag link 10 swings in an arc of a circle the plane of which is horizontal, while the rear end of this link swings in an arc the'plane of which is vertical. Furthermore, most of the con'nnon types of steering gear are in revi'u'silrile to a considerable degree, and therefore the function of the ai'itiskidding device is n'ierelyto supplement the retarding action i tl 5 ring gear at the proper instant to prevent skidding.

The time iouing of this invention to prevent skidding may be understood by consid Gllng the movements of the vehicle parts contained in two transverse planes of the veh cle, one plane passing through the pinion and the other passing through the fulcrum of the crank 11. produce skidding, cause the several vehicle parts contained in the forward plane (the plane passing through the fulcrum of crank 11) to rotate sever' l degrees with to i the opposite dimo- The forward end srahle tests have shown that this combine-ti lateral displacement andtorsion produ es suthcient binding of the rack and to prevent the forces tending to promace skidding from eilectin'g change in the J position of the front -wheels with respect-tor the chassis. Thus the resistance offered by the bindingnick and pinion, together with h" the steering mechaniim itself,

t 10 front Wheels in position. \Vhen either of the front wheels of the 'ehicle obstrihition 111 the road, this inventital-serves as an ctlirient shock absorber,

and prevents the front. wheels from clung-{ If a front wheel strikes 1 ing theili course.

an tacle which tends to change the position of the wheel, the knuckle joint '3' causes. the forward end of the drag link 10 to con:-

inence swinging around in its arcuate path.

Due to the inertia of the. steering mechanism, and the resistance produced by virtue of the partial irreversibility of thismechanisni, the first reaction caused by the. irregular move- .menl; of the front wheel is a lateral bending of the composite mcn'iber consisting of the drag link 10 and the link 17. It has been observed that a sharp blow on one front Wheel will produce this condition. The play in the joint connecting the drag; link 10 and the The forces which tend to 35 -n the rear plane pass- 90 he link ll', to swing in 95 wing of the rear wheels by hold- 1m croni: 1' permits snliicient lateral displacel'il z'l i i l: the 'in'wsrd end of linli 17 to produce the neeessmry binding action between the eel; and pinion. 6 also to be observed that when one of Wheels of the "vehicle strikes zin obroach conditions are proi'lnced miiiias those ting i /hen the which) i front wheel in passing .cle in the road, produces :2 dis ne which, in turn,

3 and the s te. g mechanism,

j to prevent skidding of the rear wheels 1" any :rnditions yet this action does interfere with the steering y turi iing t e hand wheel 7 out il 1*, it does not re v ntitm to that proechiniism, to nail i's n position so to pretne stabilizing force 1n ively small, h iniiproved lengjg i cch truism t, mther i U111, who 1:.- re

nielrein i, L n i 7 results, 1 here i V v'i I post 1V1} locking oi the it and. its operation is tn: lly on when the OllflSSlS 11 for COIiSHlQ'Jfllllo Uliitj, i one tire deflated, it Siill t vehicle with comp-urn; i (t {100 producing only :1 slight; tion of the steering inccln l he fact that; i it rfcre with the Ste 1 mechcring n'iscl'itinism the vehicle the more u, and oi the crank 11 to i u to is such as to poll the link income to bring the pinion "c intby way of c;-,-:periinents 2;

i to t not interfere With the ion of the stccring niacin enclosed in a 't'or srnnli obthe combinstion of 2!. member adapted to be fixed with respect to the chassis of :l vehicle, a second member adopted to be connected to the steering system of the vehicle, the said members being in contact with each other and arranged to cooperate so that they will bind when. they are out of alignment with each other.

In a device of the character described, the combination of a friction member, means for fixing said member to the ch. ssis of a vehicle, it second friction mei'i'iber, and means for connecting said second meniiber to the drag link of the steering system of the Vchiclc, the said -friction members being in contact with each other and arranged to cooperate so that they will bind when they are out of alignment with each other.

In a device of the character described, a "friction member, means for fixing said member to the chassis of a vehicle so that the member will extend longitudinally there- I second Eric 'on member, means ror connccting said second member to the drag link oi? the steering system of the vehicle and means for constraining said second member to move in a rectilinear path parallel to said first member, the said friction members be ing in contact with each other and arranged to cooperate so that they will bind when they are out of alignment with each other. 4. In a device of the character described, the combination of :1, friction member, means for fixing said member to the chassis of a vehicle, a rotary friction member and means :tor connecting said rotary'member to the steering system of the vehicle, said friction members being in contact With each other and arranged to cooperate so that they Will bind when they are out of alignment with each other.

In a device of the character described,

:the combination of 21- rack, means for fixing said rack to the chassis of a vehicle, a pinion 'adapted to engage the rack, means for connecting said pinion to the steering system of the vehicle, and means for holding said pinion in position on said rack, the said rack and pinion being zirrai'iged to cooperate so that they will bind when they are out of alignment with each other.

6. In a device of the character described, the combination of arack, means for securing said rack to the chassis of a vehicle, a pinion, a slide associated with said rack and said pinion for holding said pinion in position, and means for connecting said pinion to the drag link of the steering system of the vehicle, the said rack and pinion bein ar ranged to cooperate so that they will ind when thsy are out of alignment with each other.

7r In a device of the character described, the combination with a frame provided with devices .tor steering a motor vehicle. of a K guide member carried by the frame, a rotary motor vehicle, of a rack secured to the frame, member slid-ably mounted on the gnide,'and a slide inountedon the rack, a pinion carried it; i means Conn-e; ing said rotary member to the by the slide to engage the rack, and means 10 i steering den es. cminecting the diag link of the steering de- 5 8. In {L device of the character described vices with the pinion. I i 1 the combination with a frame provided with In testimony WhBTGOfIhfliX my signature devices including a draglink for steering a MICHAEL J. DAVIS. 

